Influence of Mineral Powder Content on the Fracture Behaviors and Ductility of Self-Compacting Concrete

摘要

04015147.1-04015147.14%This paper describes and discusses an experimental study on the effect of mineral filler on the fracture behavior and ductility of self-compacting concrete (SCC). Based on an experimental program, a series of three-point bending tests was carried out on 118 notched beams. SCC was prepared with various contents of mineral filler with water-to-cement (w/c) ratios of 0.47 and 0.6. For all mixes, the fracture parameters were analyzed using the work-of-fracture method (WFM) and the size-effect method (SEM) to obtain a suitable correlation between these methods that is used to calibrate fracture numerical models. Given an increase in mineral filler content and a decrease in the w/c ratio in SCC, the results yielded the following conclusions: (1) fracture energies, G_F in WFM and G_f in SEM, increase slightly; (2) the brittleness number increases; (3) the characteristic length (L_(ch)) in WFM and the fracture process zone length (C_f) in SEM decrease, which may be due to an increase in the packing density and changes in the pore size distribution; and (4) the behavior of SCC specimens, based on the size-effect curve, approaches the linear elastic fracture mechanics criterion. In addition, the results showed that there is a significant correlation between G_F and G_f values (G_F/G_f = 3.0).